Hi, you can easily get to downtown Vancouver from the airport on a city bus for about $3.50CAD.
It's very easy, and will take about half an hour. It will get you downtown and within walking distance of whatever hotel you're at.
If you want to take a taxi, it's probably about $35 to get downtown.
From your hotel, I'd just take a taxi to the cruise port. It will probably only be about $10 if your hotel is right downtown. But maybe your hotel with offer a shuttle to the ship...

I would just look at expedia.ca at the hotels available and prices.

I'd be glad to help with more, if you need
I've lived there my whole life, and I drive the bus there!